I am running the latest Docker CE, 17.09, under Windows 10 Pro, and using two different examples am getting Permission denied.
Docker site example:
docker run -d -p 80:80 --name webserver nginx
AWS site Docker example:
docker run -p 80:80 hello-world
both returned the same error.
docker: Error response from daemon: driver failed programming external connectivity on endpoint XXXXX: Error starting userland proxy: Bind for 0.0.0.0:80: unexpected error Permission denied.